TITLE:
Study on Voltage Sag Detection of Wind Power System Based on HHT
AUTHORS:
Yanqing Li, Ting Yue, Hongling Xie, Feilong Wang
KEYWORDS:
HHT; Wind Power System; Voltage Sag; Detection
JOURNAL NAME:
Energy and Power Engineering,
Vol.5 No.4B,
November
12,
2013
ABSTRACT: For the output of wind power system has the
characteristics of randomness, volatility and intermittence, the voltage of
wind power system fluctuates frequently and voltage sag is one of the most
common voltage fluctuations in wind power system. For the problem of voltage
sag of wind power system, the limitations of the detection methods such as the
square detection method, the half-wave RMS detection method and wavelet
transform are summed up, and a new detecting method named Hilbert-huang
Transform(HHT) is put forward in this paper, which can detect the voltage sag
accurately and timely. In order to solve the problem of end effect in the
process of empirical mode decompostion (EMD), a self-adaptive method named improved waveform
matching is applied in dealing with the end issue. Voltage fluctuations are reflected by two parameters named voltage amplitude and frequency of each
intrinsic mode function (IMF) in HHT. The practicality of the method is
verified by Matlab simulation.